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>I'm doing some stuff with GTK+ in a separate thread, and
properly locking with gdk_threads_enter/gdk_threads_leave()
but the display doesn't update properly. <I
CLASS="EMPHASIS"
>[GTK 2.x]</I
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><P
>For efficiency, the X window system batches up commands
and sends them to the X server in batches instead of sending
out immediately.</P
><P
>In a non-multithreaded program, you don't have to worry about
this, since the first thing that happens when control returns
to the main loop is that any outstanding X requests are 
sent to the X server.</P
><P
>However, if you are making GTK+ calls from a thread other
than the main loop, then GTK+ doesn't know when to send batched
commands out. For that reason, after making GTK+ calls 
in a separate thread, it is usually a good idea to call
gdk_flush() before gdk_thread_leave().</P
><P
>Actually, gdk_flush() is more expensive than is necessary here,
since it waits for the X server to finish outstanding commands
as well; if performance is an issue, you may want to call
XFlush() directly:</P
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>&#13;#include &#60;gdk/gdkx.h&#62;

void my_flush_commands (void)
{
  GdkDisplay *display = gdk_display_get_default ();
  XFlush (GDK_DISPLAY_XDISPLAY (display);
}</PRE
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